Induced African swine fever in feral pigs.

Feral pigs trapped in Florida were exposed by intranasal/oral inoculation or contact to African swine fever virus isolants from the Iberian peninsula and the Dominican Republic. All exposed pigs became sick and died or were killed after becoming moribund. Necropsy revealed lesions typical of African swine fever, but several pigs had marked hemorrhage surrounding the kidneys or rectum or in the gastric, hepatic, or ventral abdominal region that, in the field, might have suggested trauma or poisoning as a cause of death. Most pigs had severe lesions associated with kidney worms. Virus was detected in the blood and selected tissues of each pig, using the hemadsorption reaction in porcine monocyte cultures; direct or indirect immunofluorescence was used to confirm the diagnosis.